Hos grisar finner man flera stereotypiska beteenden, som rörbitning och svansbitning. Dessa beteenden är relativt vanliga hos grisar. En miljöberikning definieras som förbättring av ett djurs välfärd, både psykologisk och fysiologiskt, genom förändringar hos djurets omgivning. Denna studie har undersökt om miljöberikningar kan minska stereotypiska beteenden hos grisar. De två olika miljöberikningar som har använts är en jutesäck fylld med halm och en Jolly Ball™. De tre stereotypiska beteendena som studerades var rörbitning, svansbitning och bukmassage. Studien utfördes på 107st grisar uppdelade på 12 boxar, under totalt tre veckor. Alla tre stereotypiska beteenden minskade statistiskt signifikant . Detta visar att båda miljöberikningarna hade en positiv effekt på grisarna då de minskade deras stereotypiska beteenden. De interagerade mer med jutesäcken fylld med halm än vad det gjorde med Jolly Ball™.  Grisarna föredrog den miljöberikningen som var omformbar, förstörbar, ätbar, tuggbar, vilket går i linje med liknande studier. / Among fattening pigs you find several stereotypical behaviours, such as bar-biting and tail-biting. These behaviours are quite common among domestic pigs. Environmental enrichments are often used to reduce stereotypical behaviours in animals.  An environmental enrichment is defined as an improvement of an animal’s welfare, both psychologically and physiologically, through changes in the environment of the animal. With this study, different environmental enrichments were studied to see if they can reduce stereotypical behaviour among fattening pigs. The two different environmental enrichments used were a jute sack filled with straw and a Jolly Ball™. The stereotypical behaviours that were looked at were bar-biting, tail-biting and belly-nosing. The study was carried out on 107 pigs divided into 12 pig boxes, during 3 weeks in total. All three stereotypical behaviours decreased significantly. This shows that the environmental enrichments had a positive effect on the pigs, since they reduced their stereotypical behaviour. The pigs interacted more with the jute sack than they did with the Jolly Ball™.  The pigs preferred the environmental enrichment that was destructible, edible, deformable and chewable, which fits well into similar studies that have been executed.

The aim of this thesis is to provide microstructural and mechanical characterisation of α-β titanium alloys exposed to a range of thermo-mechanical conditions, in particular under-going high rate deformation at elevated temperatures, representative of the Linear Friction Welding (LFW) manufacturing process. Three α-β titanium alloys provided by Rolls-Royce are studied: Ti-64 blade, disc and Ti-6246 disc. Ti-64 and Ti-6246 show complex deformation behaviour with strain, strain rate and temperature, especially near the transus temperature, where the low temperature α phase is transformed into the high temperature β phase. The microstructure and mechanical properties evolve in an interconnected fashion, and understanding this mutual influence is necessary to better predict the behaviour of these alloys. Characterisation of the mechanical properties was performed through uniaxial compression tests at strain rates from 0.001 to 3000 s^-1, using an Instron screw-driven machine at quasi-static rates, a servo-hydraulic machine at medium rates and a Split-Hopkinson Pressure Bar and a drop-weight tower at high strain rates. The tests were performed over a range of temperatures from room temperature to 1300 °C. The main focus was on high strain rate and high temperature tests, with the development of a gravity driven direct impact Hopkinson bar, referred as a drop-weight system, which is intended to evaluate the mechanical response of metals to high strain rate loading at temperatures up to c. 1300 °C. The design and principles of operation of the system are presented, along with calibration and validation data. Preliminary tests were performed on stock Ti-64, heated at two rates: 1 and 20 °C s^-1. The evolution of the mechanical properties was analysed, focussing on the strain rate, temperature and phases dependencies. Characterisation of the microstructure was realised by performing interrupted compression tests, first at room temperature, three plastic strains, 4%, 10% and 20%, and two different strain rates, 0.001 and 2000 s^-1; then at 4% plastic strain, a strain rate of 2000 s^-1 and three elevated temperatures, 700, 900 and 1100 °C. A better understanding of the microstructure evolution with strain, strain rates and temperature, including the macrotexture and microtexture of the specimens, was obtained using Electron Backscatter Diffraction (EBSD) to characterise the texture of the undeformed and deformed materials. The better understanding of the flow stress and microstructural evolution of both Ti-64 and its individual α and β phases with various strain rates and temperatures is intended to be used in the development of more accurate models representing the behaviour of these alloys. Predicting the microstructure evolution and then the mechanical properties of a material is essential to optimise the final mechanical properties of the alloys when welded by manufacturing processes such as the LFW process.

Dans le contexte du changement global, la diminution de la disponibilité en oxygène (hypoxie) combinée à la hausse de la température sont deux phénomènes particulièrement présents dans les eaux côtières vers lesquelles les larves de poissons peuvent dériver à la fin de leur développement. Il est admis que les régulations mises en oeuvre par les organismes pour faire face à leur environnement au cours des premières étapes de leur vie peuvent avoir des conséquences sur leur trajectoire de vie ultérieure (plasticité développementale). Ainsi, l'objectif principal de cette thèse était d’évaluer si des conditions d'oxygénation (40% et 100% de saturation) combinées à des conditions thermiques (15 et 20 °C) au stade larvaire, pouvaient avoir des impacts durables sur la physiologie des futurs juvéniles de bar (Dicentrarchus labrax). Nos résultats ont révélé que les retards de croissance associés à la plus basse température et à l’hypoxie au stade larvaire induisent une croissance compensatrice. De plus, les analyses des réserves hépatiques en glycogène et en lipides ont révélé que le métabolisme des juvéniles pourrait être affecté par les conditions environnementales au stade larvaire. Par ailleurs, nos données indiquent que la capacité d'extraction de l'oxygène a été affectée chez des juvéniles en raison de déformations operculaires causées par l’exposition précoce à l'hypoxie. Enfin, l'exposition précoce à l'hypoxie induit une sur-expression à long terme de gènes de l'hémoglobine de juvéniles replacés en situation d’hypoxie. Globalement, nos résultats contribuent à faire avancer les connaissances sur la façon dont les poissons marins font face aux changements climatiques actuels. / In the context of global change, decrease in oxygen availability (hypoxia) combined with rising water temperature are especially prevalent in coastal regions, towards which marine fish larvae may drift at the end of their development. It is well admitted that the physiological regulations implemented by organisms to cope with their environment during the early life stages of life can cause profound consequences in their subsequent life-history trajectory (developmental plasticity). Therefore, the main objective of this thesis was to investigate whether ecologically relevant conditions of oxygenation (40% and 100% air saturation) combined with thermic conditions (15 and 20 °C), occurring at the last stages of larval development of European sea bass (Dicentrarchus labrax) larvae, could have long-lasting impacts on juvenile physiology. Our data showed that growth depression resulting from low temperature and hypoxic conditions at larval stage induced a subsequent compensatory growth. Moreover, our analyses of hepatic glycogen and lipid stores revealed that metabolic features of juvenile could be affected by early exposure to oxygen and temperature conditions. Furthermore, our data revealed that oxygen extraction capacity was affected due to opercular deformities caused by early exposure to hypoxia. Finally, when seabass juveniles, that have been exposed to hypoxia at larval stage, were under chronic hypoxic condition they show a long-term up-regulation of hemoglobin genes. Overall, our findings contribute to make predictions of how the marine fish communities could be altered by current climate change.

For a long time, auxiliary lights utilizing halogen or xenon light sources has been fitted in front of the car’s front grille when needing an improved high beam performance. The bigger the auxiliary light, the better its light performance has been. Today’s LED (Light Emitting Diode) technology, where several small light sources are used, has enabled a new market of auxiliary lights, smaller in size and more flexible in shape but with performance able to both match and outperform the traditional auxiliary lights. This master thesis focuses on developing an overall solution for mounting the type of LED auxiliary light commonly referred to as LED light bars on the roof of a car and aims to broaden an existing market. LED light bars are characterized by its oblong and cuboid-like shape. High-performance light bars are theft-desirable by nature as they have a high price and lack of theft security in themselves. In today’s market, there is no given solution for the attachment of roof mounted light bars without harming the car. As a result, mountings of this kind are mostly seen neither aerodynamic nor aesthetically appealing. The project has been performed according to the CDIO (Conceive, Design, Implement, Operate) phases. During the conceive phase, a comprehensive pre-study was carried out in which car, relevant theories, LED light bars, competitors and expert observations were investigated. In the design phase, ideas were developed using a number of creative methods implemented individually, in groups and in the form of a workshop. Ideas were clustered into categories and were screened prior to the implement phase. In the following phase, the ideas were combined into a concept that was defined in details. A prototype was manufactured and evaluated, after which the concept was iterated into a final solution. During the last phase, operate, all deliverables were produced at the same time as a manufacturing process was initiated. Together with Vparts, a company dedicated entirely to Volvo owners, an overall solution has been developed to enable a good-looking, anti-theft-proof, model specific and aerodynamic mounting of LED light bars onto the roofs of cars. The concept consists of a double curved light bar in combination with lockable and adjustable mounts having an aerodynamic shape. The solution is modular and includes two different versions of the mounts, which together cover 9 Volvo models, each variant consisting of four different components per side of the light bar.

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-08-17T12:44:53Z No. of bitstreams: 1 CECÍLIA ELISA DE SOUSA MUNIZ - DISSERTAÇÃO (PPGEQ) 2017.pdf: 1566496 bytes, checksum: 6a11f4784c5c418c014738b1b8624c76 (MD5) / Made available in DSpace on 2018-08-17T12:44:53Z (GMT). No. of bitstreams: 1 CECÍLIA ELISA DE SOUSA MUNIZ - DISSERTAÇÃO (PPGEQ) 2017.pdf: 1566496 bytes, checksum: 6a11f4784c5c418c014738b1b8624c76 (MD5) Previous issue date: 2017-10-05 / Com os produtos tradicionais fontes de proteína se tornando mais caros a cada dia, surge a necessidade de desenvolver novos produtos alimentícios com alto valor nutricional e que ainda assim sejam de baixo custo, podendo ser consumido pela população de todas as classes econômicas. As barras de cereais já representam uma alternativa de complemento alimentar à base de carboidratos e fibras, sendo assim, esta pesquisa teve como objetivo elaborar barras de cereais que contenham na sua composição resíduos agroindustriais, que submetidos ao processo de enriquecimento proteico por via microbiana, irão aumentar o teor proteico e nutricional deste respectivo produto, além de torna-los mais baratos. O microrganismo utilizado foi a levedura Saccharomyces cerevisiae, e os resíduos escolhidos para tal objetivo foram o bagaço do caju e as cascas de goiabas. Inicialmente fez-se o preparo dos resíduos, os quais foram secos em estufa com circulação de ar a 55±2°C até peso constante. A caracterização físico-química dos resíduos do caju e da goiaba mostrou que, estes poderiam ser submetidos ao processo fermentativo de enriquecimento proteico e posteriormente como ingredientes na elaboração das barras de cereais, apresentando teores suficiente de açúcares redutores, pectina e fibras, além de um pH adequado ao meio de cultivo. Para o enriquecimento proteico utilizou-se a levedura em uma concentração de 3%, para o resíduo do caju e de 5% para o resíduo da goiaba, sob temperatura de 30ºC durante 9h de cultivo. Tanto o resíduo do caju quanto o da goiaba teve o seu teor de proteína elevado em quatro vezes. Após a obtenção dos resíduos enriquecidos proteicamente foram elaboradas quatro formulações de barras de cereais, onde a aveia foi substituída parcialmente pelos resíduos agroindustriais, (F0) formulação de referência sem adição de nenhum dos resíduos, (F1) constituída apenas pelo resíduo do caju, (F2) constituída apenas pelo resíduo da goiaba e (F3) constituída pelos dois resíduos, goiaba e caju. As barras de cereais elaboradas foram caracterizadas físico-químicamente quanto ao teor de água, cinzas, lipídeos, carboidratos, proteína e fibra alimentar, apresentando resultados bastante satisfatórios, principalmente quanto ao teor de proteína, em torno de 12% para a formulação F1, valor este superior ao encontrado nas barras de cereais comercializadas no mercado. Posteriormente elas foram submetidas a análise microbiológica para verificar a ausência/presença de coliformes totais, coliformes fecais e salmonela sp., os resultados obtidos apresentaram contagens inferiores ás máximas estipuladas pela RDC n° 12 atendendo portanto, aos requisitos da legislação vigente. Por fim as formulações foram avaliadas sensorialmente em uma academia da cidade por um grupo de 40 julgadores os quais avaliaram os atributos: cor, aroma, sabor, textura e aceitação global, utilizando uma escala hedônica de 9 pontos, além da intenção de compra, utilizando uma escala hedônica de 5 pontos. Os resultados obtidos foram satisfatórios, para todas as barras de cereais analisadas pelos julgadores os quais afirmaram que gostaram moderadamente (7) e que possivelmente comprariam (4) caso elas fossem comercializadas. / With traditional sources of protein becoming more expensive every day, there is a need to develop new food products with high nutritional value that are still low cost and can be consumed by the population of all economic classes. The cereal bars already represent an alternative food complement based on carbohydrates and fibers, so, this research aims to elaborate cereal bars containing in their composition agroindustrial residues, which undergo the process of microbial protein enrichment, will increase the protein and nutritional content of this respective product, besides making them cheaper. The microorganism used was the yeast Saccharomyces cerevisiae, and the residues chosen for this purpose were the cashew bagasse and the guava husks. Initially the waste was prepared, which were dried in an oven with air circulation at 55 ± 2 ° C until constant weight. The physico-chemical characterization of the cashew and guava residues showed that they could be submitted to the fermentative process of protein enrichment and later as ingredients in the elaboration of the cereal bars, presenting sufficient levels of reducing sugars, pectin and fibers, besides a pH suitable for culture medium. For protein enrichment, the yeast was used at a concentration of 3% for the cashew residue and 5% for the guava residue, at a temperature of 30 ° C for 9h of culture. Both the cashew and guava residue had their protein content elevated fourfold. After obtaining the protein enriched residues, four formulations of cereal bars were elaborated, where the oats were replaced partially by the agroindustrial residues, (F0) reference formulation without addition of none of the residues, (F1) constituted only by the cashew residue, F2) constituted only by guava residue and (F3) constituted by the two residues, guava and cashew. The elaborated cereal bars were physicochemically characterized as water, ash, lipids, carbohydrates, protein and dietary fiber, presenting satisfactory results, mainly regarding the protein content, around 12% for the formulation F1, value higher than that found in cereal bars marketed on the market. Subsequently, they were submitted to microbiological analysis to verify the absence/presence of total coliforms, fecal coliforms and salmonella sp., the results obtained were lower than the maximum stipulated by RDC n° 12, thus meeting the requirements of current legislation. Finally, the formulations were evaluated sensorially in a gymnasium of the city by a group of 40 judges who evaluated the attributes: color, aroma, flavor, texture and global acceptance, using a hedonic scale of 9 points, besides the intention to buy, using a hedonic scale of 5 points. The results obtained were satisfactory for all cereal bars analyzed by the judges who stated that they liked moderately (7) and that they would possibly buy (4) if they were marketed.

SILVA, Ana Lívia Brasil. Otimização dos teores de alga Saccharina japônica E Chenopodium quinoa Wild no desenvolvimento de barra de cereais. 2015. 67 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2015 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-07T13:01:52Z No. of bitstreams: 1 2015_dis_albsilva.pdf: 2531812 bytes, checksum: 10b70485de8deb0a1d3750a0bd40d247 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-07T13:02:19Z (GMT) No. of bitstreams: 1 2015_dis_albsilva.pdf: 2531812 bytes, checksum: 10b70485de8deb0a1d3750a0bd40d247 (MD5) / Made available in DSpace on 2016-07-07T13:02:19Z (GMT). No. of bitstreams: 1 2015_dis_albsilva.pdf: 2531812 bytes, checksum: 10b70485de8deb0a1d3750a0bd40d247 (MD5) Previous issue date: 2015 / Seaweed japonica saccharine, popularly known as "Kombu" is a food rich in protein, fiber and micronutrients. This algae has antioxidant properties, anti-viral, anti-tumor, anti-inflammatory and hypoglycemic. Quinoa (Chenopodium quinoa Willd) is considered a pseudocereal whose main characteristic is the quality of its protein and is recognized by the World Health Organization (WHO) as an ideal food for its nutritional composition is higher than most cereals. The addition of these two ingredients in salt cereal bar formulation can add greater nutritional value to this product, which has shown an increasing consumption in recent years. The study aimed to prepare savory cereal bars added the saccharine japonica algae in different concentrations (2, 4, 6, 8, 10%) and quinoa (1, 2, 3, 4, and 5%), through the use of design central composite (DCC). One of the formulations of the cereal bars was selected to study storage stability, with respect to acidity and moisture and microbiological analysis, and sensory parameters at times 0, 30, 60 and 90 days. In the development of cereal bars, the formulations examined had ash contents of 4.46% to 8.04% (Formulations 9 and 4, respectively), fat 2.8% to 4.61% (Formulations 3 and 5, respectively), and protein 14.2% to 19.19% (Formulations 1 and 10, respectively). The Maoria bars showed sensory acceptance corresponding to "like slightly to like a lot," and had satisfactory results for microbiological analyzes. The formulation 5, added with 2% and 3% seaweed quinoa, achieved the best results concerning the nutritional and sensory quality, thus has been selected for the study of storage stability. The moisture and acidity remained stable after 90 days of storage, similar results were observed for the microbiological quality. According to sesorial analysis, the number 5 cereal bar is framed in sensory acceptance zone in category "like moderately" to "enjoyed". Therefore, it was concluded that the developed cereal bars can become an option for many types of diet or for those seeking a healthier lifestyle, it presented high protein and low fat, as well as showing good sensory acceptance. / A alga Saccharina japonica, conhecida popularmente como “Kombu” é um alimento rico em proteína, fibra e micronutrientes. Esta alga apresenta propriedade antioxidante, antiviral, antitumoral, anti-inflamatória e hipoglicêmica. A quinoa (Chenopodium quinoa Willd) é considerada um pseudocereal que tem como principal característica a qualidade de sua proteína, sendo reconhecida pela Organização Mundial de Saúde (OMS) como um alimento ideal, por sua composição nutricional ser superior à maioria dos cereais. A adição desses dois ingredientes na formulação de barra de cereais salgada poderá agregar um maior valor nutricional a esse produto, que vem apresentando um crescente consumo nos últimos anos. O trabalho teve como objetivo elaborar barras de cereais salgadas adicionadas da alga Saccharina japônica em diferentes concentrações (2, 4, 6, 8, 10%) e de quinoa (1, 2, 3, 4, e 5%), por meio do uso do Delineamento Composto Central Rotacional (DCCR). Uma das formulações das barras de cereal foi selecionada para o estudo de estabilidade ao armazenamento, quanto às análises de acidez e umidade e aos parâmetros microbiológicos e sensoriais, nos tempos 0, 30, 60 e 90 dias. No desenvolvimento das barras de cereal, as formulações analisadas apresentaram teores de cinzas de 4,46% a 8,04% (Formulações 9 e 4, respectivamente), gordura de 2,8% a 4,61% (Formulações 5 e 3, respectivamente), e proteína de 14,2% a 19,19% (Formulações 1 e 10, respectivamente). A maoria das barras apresentou aceitação sensorial correspondente a “gostei ligeiramente a gostei muito”, bem como tiveram resultados satisfatórios para as análises microbiológicas. A formulação 5, adicionada com 2% de alga e 3% de quinoa, obteve os melhores resultados referentes à qualidade nutricional e sensorial, desta maneira foi selecionada para o estudo de estabilidade ao armazenamento. Os teores de umidade e de acidez mantiveram-se estáveis após 90 dias de estocagem, resultado semelhante foi observado para a qualidade microbiológica. De acordo com as análises sesorial, a barra de cereal de número 5 se enquadrou na zona de aceitação sensorial na categoria “gostei moderadamente” a “gostei muito”. Portanto, concluiu-se que as barras de cereais desenvolvidas podem se tornar uma opção para diversos tipos de dieta ou para quem procura uma vida saudável, pois apresentou elevado teor de proteínas e baixo teor de gordura, além de apresentar boa aceitação sensorial.

Made available in DSpace on 2014-06-11T19:26:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-03Bitstream added on 2014-06-13T20:14:49Z : No. of bitstreams: 1 santos_vc_me_rcla.pdf: 1357104 bytes, checksum: 93f8d2931c8ea5facacb9de9abe21ee3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O rio Paraná, em seu trecho natural, possui padrão multicanal caracterizado por canais secundários de diferentes ordens, separando diversas ilhas e barras fluviais. As barras fluviais são formas semi-submersas associadas à disponibilidade de sedimentos e a um dinamismo temporal cujas dimensões são controladas pelo fluxo e pela profundidade. Neste estudo, pretende-se compreender os processos que promovem a formação, desenvolvimento e movimentação de uma barra de soldamento situada junto à ilha Santa Rosa, no rio Paraná, município de Porto Rico - PR. Para alcançar os objetivos propostos, foram realizados levantamentos de parâmetros hidráulicos, morfométricos e granulométricos. Nos dados levantados dos parâmetros hidráulicos, verificou-se que a presença da ilha Santa Rosa, juntamente com barra fluvial, divide o canal em dois setores de dinâmica hidráulica e sedimentar distintas. O canal principal conduz a maior parcela da vazão, é mais energético, enquanto o canal secundário apresenta valores inferiores nestes dois parâmetros. A separação do fluxo também acarreta na formação de correntes divergentes à direção principal do canal, favorecendo a diminuição da velocidade e, consequentemente, a deposição de sedimentos no entorno da ilha Santa Rosa. Averiguou-se que a morfologia da barra está diretamente vinculada às flutuações de vazão do rio Paraná: em período de águas altas há maior retrabalhamento da forma, já no período de águas médias, esta se preservou parcialmente, inclusive com afloramento em parte. Quanto aos sedimentos, as partículas de diâmetro fino distribuem-se em locais de maior velocidade de fluxo e profundidade (talvegue) em ambos os períodos analisados As partículas de diâmetro médio a grosso encontram-se no período de águas altas distribuídas pela área estudada; já no período de águas médias, estes sedimentos... / The Paraná River, in its natural stretch, has a multichannel pattern characterized by secondary channels of different orders, which separates several islands and bars. The bars are forms semi-submerged associated with the availability of sediment and a temporal dynamic, whose dimensions are controlled by the flow and depth. This study intends to understand the processes which promote formation, development and movement of the annexation bar associated to the Santa Rosa Island, located on Paraná River, near to Porto Rico - PR. To achieve the proposed aims, surveys were carried out in hydraulic, morphometric and granulometric parameters. In the data hydraulic parameters survey it was found that the presence of Santa Rosa Island along with bar divides the river channel in two sectors of distinct dynamic hydraulic and sediment. The main channel leads to a higher portion of the flow, it is more energetic, while the secondary channel has lower values in these two parameters. The separation of the flow also causes the formation of divergent currents towards the main channel, favoring the decrease in velocity and consequent deposition of sediments near to Santa Rosa Island. It was found that the morphology of the bar is directly linked to fluctuations in the flow of the Paraná River, during periods of high water there is more reworking, since in this average water period partially preserved its shape, emerging in part. As for sediment, the fine diameter particles are distributed in areas of higher flow velocity and depth (thalweg) in both analyzed periods. From medium to coarse diameter particles are, in the high-water period, distributed in the studied area, although in the average water period these sediments are located in low flow velocity and depth (Bar and Secondary Channel). Specific stream power and shields parameter values are larger in the main channel in both periods, indicating... (Complete abstract click electronic access below)

Made available in DSpace on 2016-06-02T20:02:57Z (GMT). No. of bitstreams: 1 6458.pdf: 5523001 bytes, checksum: 13a03e09a64c7737467c2e1eee8e86bc (MD5) Previous issue date: 2014-10-17 / The dissertation presents a proposal for teaching the content of fractions to a 7th grade classroom of basic education, based on a concrete didactical material, Fraction Case , and the Bar Model inspired in Singapore Mathematics, focused on the conceptual understanding along with basic operation skills. The motivation to this work was the recognition of great difficulty in learning with understanding of rational numbers, shown by the students of basic education across the grades. The learning of rational numbers is of fundamental importance to the accomplishment of the mathematics curriculum of basic education. We adopted the Fraction Case and the Bar Model because they actually offer the possibility of visualizing concrete representation of ideas that underline the subject of fractions. The proposed activities were inspired by the didactical ideas and activities in Baldin & Malagutti (2006), and they aim at the understanding of the concept of equivalent fractions together with the basic operations of addition, subtraction, multiplication and division of fractions, starting from the perspective of the part-whole relationship. We bring out the outcome resulted from the application of activities in three classrooms of 7th grade students of a private school of city of Bauru. / Apresentamos neste trabalho uma proposta de ensino do conteúdo de frações para uma turma de 7º ano, baseada na utilização de um material concreto intitulado Estojo das frações e do Modelo de Barras da Matemática de Singapura, e centrada na consolidação dos conceitos e das operações básicas. A realização deste trabalho foi motivada por uma constatação da enorme dificuldade de aprendizagem e compreensão dos números racionais apresentada por alunos de diversas séries do ensino fundamental. A aprendizagem dos números racionais é de fundamental importância para o desenvolvimento do conteúdo curricular da matemática do ensino fundamental. O Estojo de frações e o Modelo de Barras foram utilizados, pois oferecem a possibilidade de visualizar concretamente os conceitos relacionados ao tema de frações. As atividades propostas foram baseadas nas ideias didáticas e atividades do material de Baldin e Malagutti (2006), e buscam a compreensão do significado de frações equivalentes e das operações de adição, subtração, multiplicação e divisão de frações a partir do significado parte-todo. Trazemos também os resultados obtidos a partir da aplicação dessa proposta com três turmas de 7º ano de uma escola particular de Bauru.

Made available in DSpace on 2014-06-11T19:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-05-29Bitstream added on 2014-06-13T18:45:40Z : No. of bitstreams: 1 grotta_dcc_dr_jabo.pdf: 473302 bytes, checksum: f8cdc0255abc578da01bc3a223137e5e (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo buscado com o desenvolvimento do trabalho foi obter informações quanto às melhores alternativas para o sistema de semeadura direta em regiões com características semelhantes às de Jaboticabal/SP, na cultura do milho, em diferentes manejos de culturas de cobertura do solo. O experimento foi conduzido na área experimental do Laboratório de Máquinas e Mecanização Agrícola (LAMMA) da UNESP/Jaboticabal. Avaliou-se o desempenho do conjunto trator-semeadora-adubadora, o desenvolvimento de um híbrido simples de milho (DKB 390), e as perdas na colheita mecanizada em função de 2 culturas de cobertura crotalária (Crotalária juncea L.) e mucuna preta (Mucuna aterrina L.), manejadas de 3 formas, sendo duas mecânicas (triturador de palhas e rolo-faca) e uma química (herbicida via pulverizador) com a cultura do milho semeada a 5 cm de profundidade e deposição de adubo em 3 profundidades (11, 14 e 17 cm) totalizando 18 tratamentos com 4 repetições com delineamento em blocos ao acaso, em esquema fatorial. Os resultados evidenciaram que a força de tração na barra foi menor nas profundidades 11 e 14 cm do sulcador de adubo, e o mesmo ocorreu para a força de tração na barra por fileira de semeadura, força de pico na barra de tração, potência na barra de tração, potência na barra por fileira de semeadura, consumos volumétrico e ponderal. O consumo específico foi maior na profundidade de 11 cm do sulcador de adubo. A distribuição longitudinal de plantas não foi influenciada pelos fatores. Os fatores cultura, manejo e profundidade não influenciaram as variáveis, fluxo de grãos, fluxo de material não grão, fluxo total e perdas totais. As perdas totais não foram influenciadas por nenhum dos fatores estudados. / The objective sought with the development of the work was to obtain information on the best alternatives to the no-tillage system sowing in regions with similar characteristics to those of Jaboticabal / SP, in the corn crop in different management cultures of soil cover. The experiment was conducted in the experimental area of the Laboratory of Machinery and Agricultural Mechanization (LAMMA) of São Paulo University State. It was evaluated the performance of all tractor-seeder-fertilizer, the development of a simple hybrid maize (DKB 390), and losses in mechanized harvesting crops in function of 2 coverage cultures (Crotalária juncea L.) and black mucuna ( Mucuna aterrina L.), managed in 3 ways, two mechanical (crusher of straw and roll-knife) and a chemical (herbicide spray route) with the corn crop sown to 5 cm deep and deposition of fertilizer in 3 depths ( 11, 14 and 17 cm) totaling 18 treatments with 4 repetitions with design in randomized blocks in factorial plots. The results showed that the force of traction in the bar was lower at depths of 11 to 14 cm stem of fertilizer, and the same occurred for the traction force on the bar by row of sowing, the power peak in the bar of traction, potency on the traction bar, potency on the traction bar by the row of sowing, consumption volumetric and weight. The specific consumption was higher in the depth of 11 cm from steam of fertilizer. The longitudinal distribution of plants was not influenced by factors. The factors culture, management and depth did not influence the variables of grain flow, flow of material non-grain, total flow and total losses. The total losses were not affected by any of the factors studied.

O preparo inicial do solo tem grande importÃncia para a produÃÃo agrÃcola, essa atividade à geralmente realizada por traÃÃo animal na agricultura familiar. Nesse trabalho estudou-se a utilizaÃÃo de tratores de rabiÃas como fonte de otimizaÃÃo do trabalho no campo. O experimento foi desenvolvido com um trator de rabiÃas com um arado acoplado na Universidade Federal do Cearà com o objetivo de avaliar a eficiÃncia energÃtica do trator de rabiÃas acoplado ao arado de disco utilizando trÃs marchas (1Â, 2 e 3Â) em um Argissolo Vermelho Amarelo, avaliou-se tambÃm o empolamento do solo e os nÃveis de ruÃdo com a mÃquina parada em diferentes raios de afastamento (1, 2, 5 e 10 m), e com o trator de rabiÃas em movimento utilizando trÃs rotaÃÃes (810, 1.040 e 1.360 rpm). Para obtenÃÃo de dados sobre a eficiÃncia energÃtica utilizou-se um trator de rabiÃas, instrumentado com sensores indutivos nas rodas para medir a patinagem dos rodados, fluxÃmetro para medida do consumo de combustÃvel e cÃlula de carga para obtenÃÃo da forÃa de trabalho na barra de traÃÃo. Para instalar a cÃlula de carga e obter estabilidade do implemento foi necessÃrio utilizar um comboio, onde o conjunto percorria um espaÃo 25 m com trÃs repetiÃÃes em cada marcha para as coletas dos dados. O empolamento do solo foi calculado atravÃs de dados obtidos com o perfilometro no campo e os nÃveis de ruÃdo foram medidos com dosÃmetro e decibelimetro. As variÃveis estudadas foram consumo horÃrio de combustÃvel (L.h-1), consumo especÃfico de combustÃvel (g.kW.h-1), patinagem dos rodados (%), forÃa de traÃÃo na barra (kN), velocidade de trabalho (m.s-1) e potÃncia disponÃvel (kW). Esses dados foram avaliados com o arado realizando trabalho e com o implemento erguido para ser feito de comparaÃÃo calculou-se as diferenÃa (resultados com o implemento arando, menos os resultados com o arado sem realizar trabalho), para estudo das mÃdias obtidas. A anÃlise dos dados foi realizada utilizando estatÃstica descritiva utilizando o programa computacional Assistat 7.6 beta. Os resultados mostraram que os valores mÃdios da patinagem foram de 10 % (1 marcha), 12 % (2 marcha) e 18 % (3 marcha). Os valores mÃdios encontrados para o arado realizando trabalho para o consumo horÃrio de combustÃvel foi de 5,45 L.h-1 (1 marcha), 4,22 L.h-1 (2 marcha) e 2,54 L.h-1 (3 marcha); o consumo especÃfico de combustÃvel foi de 3004,98 g.kW.h-1 (1 marcha), 4343,88 g.kW.h-1 (2 marcha) e 5787,91 g.kW.h-1 (3 marcha); a potÃncia foi de 1,54; 0,83 e 0,38 kW para a 1Â, 2 e 3 marcha respectivamente e as mÃdias da velocidade de deslocamento foram de 0,32 m.s-1 (1 marcha), 0,41 m.s-1 (2 marcha) e 0,44 m.s-1 (3 marcha). Os valores mÃdios encontrados para o momento em que o arado nÃo realizava trabalho, ou seja, o implemento estava erguido foi para o consumo horÃrio de combustÃvel de 6,58 L.h-1 (1 marcha), 5,98 L.h-1 (2 marcha) e 4,20 L.h-1 (3 marcha); o consumo especÃfico de combustÃvel apresentou valores de 3514,09 g.kW.h-1 (1 marcha), 4728,22 g.kW.h-1 (2 marcha) e 5787,91 g.kW.h-1 (3 marcha); a potÃncia foi de 1,54 kW (1 marcha), 0,83 kW (2 marcha) e 0,38 kW (3 marcha) e as mÃdias da velocidade de deslocamento foram de 0,27; 0,33 e 0,40 m.s-1 para a 1Â, 2 e 3 marchas respectivamente. O empolamento do solo chegou a 75 % (2 marcha) e obteve valores de aproximadamente 64 % para a 1 e 3 marcha. E os nÃveis de ruÃdo encontrados utilizando o dosimetro foram de 95,7 dB(A) (1 marcha), de 98,2 dB(A) (2 marcha) e 98,8 dB(A) (3 marcha). Os nÃveis mÃdios de ruÃdo encontrados com o auxilio do decibelimetro foi de 76,71; 77,38 e 80,80 dB(A) para as rotaÃÃes de 810, 1.040 e 1.360 rpm respectivamente. Recomenda-se o uso de protetores auriculares ou a diminuiÃÃo da carga horÃria de trabalho para o operador que esteja trabalhando diretamente com o trator de rabiÃas. / The initial tillage has great importance for agricultural production. This activity is usually performed by animal traction in family farming. In this paper, we studied the use of handlebar tractors as a source for field work optimization. The experiment was conducted with a handlebar tractor with a plow attached to it at the Federal University of CearÃ. The goal was to evaluate the energetic efficiency of the handlebar traitor attached to the disc plow, using three gears (1st, 2nd, 3rd) in a red, yellow argisoil. It was also evaluated the soil shoaling and the noise levels with the machine both stopped in different rays of distances (1, 2, 5 and 10 meters), and with handlebar traitor in movement, using three different number of turns (810, 1040 and 1360 rpm). To obtain data about energetic efficiency, it was used a handlebar traitor, an instrument with inductive sensors on wheels to measure the wheelsets slippage, a flowmeter to measure the fuel consumption and a loading cell to obtain the workforce in the drawbar. To install the loading cell and obtain the implement stability, it was necessary to use a train, in which the set traveled 25m with three repetitions in each gear to the collecting of the data. The soil shoaling was calculated through the data obtained in the field by a profilometer, and the levels of noise were measured with a dosimeter and a decibelimeter. The studied variables were the hourly fuel consumption (L.h-1), the specific fuel consumption, (g.kW.h-1), the wheelsets slippage (%), traction force in the bar (kN), work speed (m.s-1) and available power (kW). These data were evaluated with the plow working and with the implement raised to be compared. We calculated the difference (results with the implement plowing minus the results with the plow not working) to study the obtained averages. Data analysis was performed using descriptive statistics using the computer program Assistat 7.6 beta. The results showed that the average rates of slippage were 10% (1st gear), 12 % (2nd gear) and 18% (3rd gear). The average rates for the plow while it was working for the hourly fuel consumption were 5,45 L.h-1 (1st gear), 4,22 L.h-1 (2nd gear) and 2,54 L.h-1 (3rd gear); the specific fuel consumption was 3004,98 g.kW.h-1 (1st gear), 4343,88 g.kW.h-1 (2nd gear) and 5787,91 g.kW.h-1 (3rd gear); the power was 1,54; 0,83 and 0,38 kW for 1st, 2nd and 3rd gear respectively, and the movement speed averages were 0,32 m.s-1 (1st gear), 0,41 m.s-1 (2nd gear) and 0,44 m.s-1 (3rd gear). The average rates for the hourly fuel consumption that were found for the moment when the plow was not working, that is, the implement was raised, were 6,58 L.h-1 (1st gear), 5,98 L.h-1 (2nd gear) and 4,20 L.h-1 (3rd gear); the rates for the specific fuel consumption were 3514,09 g.kW.h-1 (1st gear), 4728,22 g.kW.h-1 (2nd gear) and 5787,91 g.kW.h-1 (3rd gear); the power was 1,54 kW (1st gear), 0,83 kW (2nd gear) and 0,38 kW (3rd gear), and the movement speed averages were 0,27; 0,33 and 0,40 m.s-1 for 1st , 2nd and 3rd gears respectively. The soil shoaling achieved the rates 75 % (2nd gear) and, approximately, 64 % for the 1st and 3rd gears. And the levels of noise that were found by the usage of the dosimeter were 95,7dB(A) (1st gear), 98,2dB(A) (2nd gear) and 98,8 dB(A) (3rd gear). The average levels of noise that were found by the usage of the decibelimeter were 76,71; 77,38 and 80,80 dB(A) for the turns 810, 1.040 e 1.360 rpm respectively. It is advised the use of headphones or the decreasing of the working hours for the operator who is working directly with the tractor handlebars.